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            <h2 class="title" style="clear: both"><a id="envset_cache_max"></a>DbEnv::set_cache_max()</h2>
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      <pre class="programlisting">#include &lt;db_cxx.h&gt;

int
DbEnv::set_cache_max(u_int32_t gbytes, u_int32_t bytes); </pre>
      <p>
         Sets the maximum cache size in bytes. The specified size is
         rounded to the nearest multiple of the cache region size, which is
         the initial cache size divided by the number of regions specified
         to the <a class="xref" href="envset_cachesize.html" title="DbEnv::set_cachesize()">DbEnv::set_cachesize()</a> method.  If no value is
         specified, it defaults to the initial cache
         size.
    </p>
      <p>
         The database environment's maximum cache size may also be
         configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax of
         the entry in that file is a single line with the string
         "set_cache_max", one or more whitespace characters, and the
         maximum cache size in bytes, specified in two parts: the gigabytes
         of cache and the additional bytes of cache. Because the
         <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the database environment is opened,
         it will silently overrule configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DbEnv::set_cache_max()</code> method configures a database environment,
         not only operations performed using the specified 
         <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>  handle.
    </p>
      <p>
         The <code class="methodname">DbEnv::set_cache_max()</code> method must be
         called prior to opening the database environment.
    </p>
      <p>
         The <code class="methodname">DbEnv::set_cache_max()</code> <span>
            
            <span>
                method either returns a non-zero error value or throws an
                exception that encapsulates a non-zero error value on
                failure, and returns 0 on success.
            </span>
        </span>
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              <h3 class="title"><a id="idp8784384"></a>Parameters</h3>
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                <h4 class="title"><a id="idp8783736"></a>gbytes</h4>
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          <p>
                         The  <span class="bold"><strong>gbytes</strong></span> parameter specifies the number of
                         bytes which, when added to the <span class="bold"><strong>bytes</strong></span>
                         parameter,  specifies the maximum size of the cache.
                     </p>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idp8763832"></a>bytes</h4>
              </div>
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          <p>
                         The  <span class="bold"><strong>bytes</strong></span> parameter specifies the number of
                         bytes which, when added to the <span class="bold"><strong>gbytes</strong></span>
                         parameter,  specifies the maximum size of the cache.
                     </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp8774672"></a>Errors</h3>
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        <p>
                         The <code class="methodname">DbEnv::set_cache_max()</code> <span>
            
            <span>
                method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> 
                exception, encapsulating one of the following non-zero errors, or return one
                of the following non-zero errors:
            </span>
        </span>
                    </p>
        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idp8793848"></a>EINVAL</h4>
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          <p>
                An invalid flag value or parameter was specified.
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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          <div>
            <div>
              <h3 class="title"><a id="idp8791872"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
                <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>  
            </p>
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              <h3 class="title"><a id="idp8780048"></a>See Also</h3>
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          </div>
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        <p>
                     <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> 
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